Higher fatty alcohols



Jan. 1, 1957 w. e. TOLAND ET AL 2,776,323

HIGHER FATTY ALCOHOLS Filed July 5, 1955 ALCOHOL HYDROGEN SEPARATOR FATw 3 z I. CC I CATALYST 3 5 ESTER 0 INTERCHANGE J SEPARATOR U D Q gCATALYST RECYCLE Z 0 p CATALYST Z U O O (I 2 CATALYST z: HYDROGENATIONHYDROGEN ,5 SEPARATOR i INVENTORS WILL/AM G. TOLAND IRVING E. LEV/NEATTORNEYS for example in U. S. Patent 1,839,974; such metals as cadmium,silver, tin and their oxides, as well as the oxides of zinc, chromium,magnesium and manganese; and the ruthenium-containing hydrogenationcatalysts as described in U. S. Patent 2,607,807.

Hydrogenation can be effected at a temperature within about the range of400 to 700 F. and pressures within about the range of 500 to 5000pounds, for a period of time varying from a few minutes and longer, e.g., 60 minutes, with about /2% to of catalyst based on the ester, thecatalyst being suspended in the ester or employed in fixed bed overwhich the ester is passed.

In order to illustrate the practice of the invention reference is madeto the accompanying drawing which is a schematic block diagram showingthe zones of ester interchange, hydrogenation, separation and recycle ofhydrogenation products and catalyst.

Referring now to the drawing, the fat, e. g., tallow containing theester interchange catalyst, e. g., litharge, is fed to the top of theester interchange zone, and the higher fatty alcohol, e. g., tallowalcohol produced in a subsequent step of the process, hereinafter to beshown, near the bottom. As the fat travels down the ester interchangezone, under interchange conditions hereinabove described, the esterinterchange reaction occurs with the tallow alcohol distilling up thecolumn forming glycerine and the tallow acid-tallow alcohol ester. Atthe reaction temperature, e' g., 400 F., glycerine, and excess tallowalcohol are distilled into a separator where two easily separable phasesof tallow alcohol and glycerine are formed, hydrogen gas beingcirculated through the reactor to maintain the partial pressurenecessary to distill the alcohol and glycerine at the reactiontemperature.

The tallow acid-tallow alcohol ester collects at the base I interchangezone, and the ester passed into the hydrogenation zone. Catalyst, e. g.,copper chromite, is contacted with incoming ester and hydrogenintroduced near the bottom of the hydrogenation zone, and the tallowacid-tallow alcohol ester hydrogenated under the conditions hereinabovegiven. Following hydrogenation, catalyst is removed from thehydrogenation products and returned to the hydrogenation zone with anycatalyst makeup. The hydrogenation products containing higher fattyalcohol are conducted to the ester interchange zone for use in the esterinterchange reaction earlier described.

Obviously many modifications and variations of the invention, ashereinbefore set forth, may be made without departing from the spiritand scope thereof and, therefore, only such limitations should beimposed as are indicated in the appended claims.

We claim:

1. Process for the production of higher fatty alcohols which comprisescontacting a fat with a higher fatty alcohol under transesterifyingconditions in a distillation zone, withdrawing an overhead fractioncomprising fatty alcohol and glycerine and a bottoms fraction comprisinga higher fatty alcohol ester of a fatty acid from the distillation zone,contacting the bottoms fraction with hydrogen in the presence of ahydrogenation catalyst under hydrogenating conditions in a hydrogenationzone and passing the hydrogenation reaction product into thedistillation zone together with further quantities of fat.

2. Process according to claim 1 wherein the hydrogenation catalyst is acopper chromite.

3. Process for the production of higher fatty alcohols which comprisesheating a fat with a stoichiometric excess of a higher fatty alcohol ina distillation zone at a temperature between about 300 and 600 F. underreduced pressure in the presence of an ester interchange catalyst,withdrawing an overhead fraction comprising fatty alcohol and glycerineand a bottoms fraction comprising a higher fatty alcohol ester of afatty acid from the distillation zone, contacting the bottoms fractionwith a hydrogenation catalyst at elevated temperatures and pressures toproduce a hydrogenation product containing the higher fatty alcohols,and passing said hydrogenation product into the distillation zonetogether with further quantities of fat.

4. Process according to claim 3 wherein the bottoms fraction iscontacted with a hydrogenation catalyst at a temperature within therange of 400 F. to 700 F. and at pressure within about the range of 500to 5000 pounds.

5. Process according to claim 4 wherein the ester interchange catalystis litharge.

6. Process according to claim 3 wherein the hydrogenation catalyst is acopper chromite.

7. Process according to claim 6 wherein the fat is tallow.

8. Process according to claim 7 wherein the fatty alcohol and fat isintroduced into the interchange zone in a mole ratio of from greaterthan 3 to 1 up to 7 to l.

9. Process for the production of higher fatty alcohols which comprisescontacting a fat with a higher fatty alcohol under transesterifyingconditions, fractionally distilling the transesterification reactionproduct to separate glycerine and fatty alcohol overhead and to producea bottoms fraction rich in fatty alcohol ester of fatty acid, contactingthe bottoms fraction with hydrogen in the presence of a hydrogenationcatalyst under hydrogenating conditions and then contacting at least amajor proportion of the hydrogenation reaction product with furtherquantities of fat under transesterifying conditions.

No references cited.

1. PROCESS FOR THE PRODUCTION OF HIGHER FATTY ALCOHOLS WHICH COMPRISESCONTACTING A FAT WITH A HIGHER FATTY ALCOHOL UNDER TRANSESTERIFYINGCONDITIONS IN A DISTILLATION ZONE, WITHDRAWING AN OVERHEAD FRACTIONCOMPRISING FATTY ALCOHOL AND GLYCERINE AND A BOTTOMS FRACTION COMPRISINGA HIGHER FATTY ALCOHOL ESTER OF A FATTY ACID FROM THE DISTILLATION ZONE,CONTACATING THE BOTTOMS FRACTION WITH HYDROGEN IN THE PRESENCE OF AHYDROGENATION CATALYST UNDER HYDROGENATING CONDITIONS IS AHYDROGERNATION ZONE AND PASSING THE HYDROGENATION REACTAION PRODUCT INTOTHE DISTILLATION ZONE TOGETHER WITH FURTHER QUANTITIES OF FAT.